Britney Spears pulled those spandex shorts right down today and managed to defy gravity while doing so. The 39-year-old pop princess was back to her iconic L.A. home dance moves on Tuesday, with a video shared to her Instagram both delighting and, it would seem, worrying her 27.2 million followers. Britney, who danced out 2020 in skimpy undies, kept up the signature wardrobe today, with the "Toxic" singer delivering sultry moves, killer spins, and a little tugging for good measure, and it's all fans can talk about.